OPTICAL PROJECTION LENS SYSTEM

摘要

PURPOSE: An optical projection lens system is provided, which is for photolithography used in production of micro structured device comprising an integrated circuit and a semiconductor device. CONSTITUTION: A first lens group(G1) having a positive refracting power; a second lens group(G2) which has a negative refracting power and consists of a waist(37) having a minimum diameter of radiation to be propagated; and another lens array(G3) which is arranged following the second lens group and has a positive refracting power are provided in the propagation direction, and a lens having an aspherical surface(31) is arranged in front of the waist(37). Preferably only the second lens group(G2) contains an aspherical surface(31). The lens having a aspherical surface(31) is a concave lens.